Mumbai, 27th May 2023: The Mumbai Municipal Corporation has embarked on the ambitious ‘Mithi River Water Quality Improvement’ project, aiming to enhance the water quality of the Mithi River by treating several lakh liters of water and reintroducing it back into the river. The municipal corporation asserts that the project has led to significant improvements in the water quality, and as a result, fish have started reappearing in certain stretches of the Mithi River.
The project, under the guidance of Municipal Commissioner Iqbal Singh Chahal and Additional Municipal Commissioner (Projects) P. Velrasu, focuses on the Mithi River, which spans a length of 17.84 kilometers from its origin in Mumbai to its convergence with the Arabian Sea through the Mahim Bay. The river’s catchment area spans approximately 7,295 hectares, with the primary water source being the discharge from Vihar and Powai Lakes in the Sanjay Gandhi National Park.
Following the devastating floods in Mumbai on July 26, 2005, the Mithi River Development and Protection Authority (MRDPA) was established on August 19, 2005, under the chairmanship of the Chief Minister. In line with the recommendations of the Central Water and Power Research Center (CWPRS) and the Satyasodhan Committee, the widening, deepening, construction of protection walls, and service road development of the Mithi River were undertaken in two phases, most of which have been completed.
Over time, the Mithi River has faced challenges such as solid waste accumulation, sewage contamination, and encroachments, causing concerns about its survival. Safedpul Nala, Marol Bapat Nala, and Vakola Nala join the Mithi River, making it resemble a large stream rather than the flowing and prosperous river it once was.
The ‘Mithi River Development and Pollution Control Project’ includes a water quality improvement initiative that has been operational since January 2023 in the Powai area, with a capacity to treat 80 lakh liters of water per day. The treated water is subsequently released back into the Mithi River, resulting in a positive impact on its water quality. The Municipal Corporation claims that this initiative plays a crucial role in preserving the river’s biodiversity and restoring its natural equilibrium.
The process of treating Mithi River’s wastewater involves pumping water to the project site through a canal connected to the river, aided by hydraulics and gravity. Around 59 interconnected ‘roboholes’ (previously known as ‘manholes’) facilitate the water transfer. The water undergoes a three-stage treatment process, including primary, secondary, and tertiary treatments. The primary stage separates the sewage from the water, while the secondary stage removes fine particles and metals. In the tertiary stage, impurities and odors are eliminated, followed by a final purification process utilizing UV rays. The purified water is then released back into the Mithi River.
Notably, the ‘Mithi River Water Quality Improvement’ project operates in the Powai area, encompassing locations such as Filterpada, Morarji Nagar, and the Mithi River area. Sewage from these areas is treated, resulting in purified water that is reintroduced into the Mithi River, contributing to the conservation of fish and other aquatic organisms.